Just upped my Synthroid dosage from 50 mcg to 62.5 mcg:
My endo did an ultrasensitive TSH after 6 weeks w/o FT4 and FT3 and it came out to be 1.63.
My OB/GYN ran a regular TSH and it was 2.7
In the same week with all these tests, I went to an independent lab and paid for the TSH, FT4, FT3 with my own money: TSH=2.47 FT3=2.5 (2.0-4.4), FT4=1.56 (.82-1.77).
This is puzzling me and I still have a bit of hypo symptoms but not as bad as when I was on 50 mcg.
TSH fluctuates throughout the day in the body's attempts to maintain stable thyroid hormone levels. Sammy64, thanks for your quick and very informed response, however, All lab tests were done around 10 AM.
That said, your FreeT4 level is in a good place but, your FreeT3 level would be too low for 98% of the population. This can be remedied by the addition of T3 - would your doctor consider Cytomel? I have tried Cytomel, and it made me feel really buzzed even at 2.5mcg per day. I even used Armour and that didn't work well for me. I am better on a T4-only prescription than combination. Do not know why but my body is better on T4 alone.
Just got a call from endo's office and they are raising me to 75 mcg Synthroid.
I don't know if this is a medically acceptable explanation but I think time of the month can affect your TSH (if you are still menstruating). High estrogen levels bind thyroid hormone and result in the pituitary having to raise TSH levels in order to stimulate more thyroid hormone production. I *think* TSH would be highest right before ovulation and lowest during the early days of menses, as well as 7 days after ovulation (when progesterone is theoretically highest). Estrogen suppresses thyroid function and progesterone/ testosterone stimulate thyroid function (one of the reasons men are less likely to be hypoT)
You may also find variation in lab values from one lab to the next. I think it depends on the methods they use to calculate hormone levels. Some labs are less discriminatory in filtering out what looks like TSH or thyroid hormone. My understanding is that you can rely on the "worse" lab result because the methods of calculation would result in overestimating FT3/ FT4 and underestimating TSH. Don't quote me on that one though ;-) Wish I could remember where I read these things.
You might be right and I didn't think about this as I always think my hormones are not off kilter. These last 2 cycles I have an ovarian cyst with a CD2 of E2=311. That is skyrocket high. Not helping me at all since I am TTC.